The Ag/Pt(110) model catalyst was prepared by evaporating silver on Pt(110). Adsorption and reaction of CO and O2 on Ag/Pt(110) surface were studied in situ by photo-emission electron microscopy (PEEM) during the pres...The Ag/Pt(110) model catalyst was prepared by evaporating silver on Pt(110). Adsorption and reaction of CO and O2 on Ag/Pt(110) surface were studied in situ by photo-emission electron microscopy (PEEM) during the pressure range of 10-5-10-2 Pa at 480 K. The Ag/Pt(110) surface consisted of Pt(110), AgPt interface and Ag area after annealing at 500 K. The dosing pressure of CO and O2 had a larger influence on their adsorption on the Ag area than on the Pt(110) and AgPt interface. Small Pt clusters formed on the Ag area and AgPt interface, which had a stronger ability to adsorb CO than Pt(110) terrace. The existence of Ag had an obvious influence on the kinetic of CO oxidation on Pt(110). No pattern was observed on the AgPt interface under the same condition when the formation of reaction-diffusion waves occurred on Pt(110).展开更多
The underpotential adsorption of hydrogen (HUPD) is one of the most attractive fields in surface electrochemistry and electrocatalysis. In this work, the hydrogen adsorption on polycrystalline platinum electrode exper...The underpotential adsorption of hydrogen (HUPD) is one of the most attractive fields in surface electrochemistry and electrocatalysis. In this work, the hydrogen adsorption on polycrystalline platinum electrode experimentally as well as on single crystal Pt(110) and Pt(100) electrode theoretically were studied. The effect of forced convection on the adsorption and desorption process of hydrogen was studied through adjusting the sampling rate of the microporous sampler closing to the surface of the platinum electrode immersed in dilute sulfuric acid solution. The relationship between HUPD and surface structure sensitivity was built quantitively. The DFT simulation shows that the adsorption strength of hydrogen on Pt(100), due to the lower adsorption energy, is weaker than that on Pt(110). Moreover, the bridged position of hydrogen on Pt(100) and the short-range bridged position on Pt(110) were found to be the optimal adsorption sites. The study of forced convection on the electrode surface promotes the HUPD research from static process to a convective mode and also provides a new strategy to investigate the hydrogen adsorption in solution.展开更多
The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2 modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is nea...The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2 modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.展开更多
基金financial support from the National Natural Science Foundation of China(No.21973013 and No.21673040)the National Natural Science Foundation of Fujian Province,China(No.2020J02025)+3 种基金the“Chuying Program”for the Top Young Talents of Fujian Provincesupported financially through a NWO/CW TOP grant(No.715.017.001)by a grant of supercomputer time from NWO Exacte en Natuurwetenschappen(NWO-ENW,No.2019.015)the National Science Foundation(No.CHE1951328)。
基金This work was supported by the National Natural Science Foundation of China (Grant No. 29525305).
文摘The Ag/Pt(110) model catalyst was prepared by evaporating silver on Pt(110). Adsorption and reaction of CO and O2 on Ag/Pt(110) surface were studied in situ by photo-emission electron microscopy (PEEM) during the pressure range of 10-5-10-2 Pa at 480 K. The Ag/Pt(110) surface consisted of Pt(110), AgPt interface and Ag area after annealing at 500 K. The dosing pressure of CO and O2 had a larger influence on their adsorption on the Ag area than on the Pt(110) and AgPt interface. Small Pt clusters formed on the Ag area and AgPt interface, which had a stronger ability to adsorb CO than Pt(110) terrace. The existence of Ag had an obvious influence on the kinetic of CO oxidation on Pt(110). No pattern was observed on the AgPt interface under the same condition when the formation of reaction-diffusion waves occurred on Pt(110).
基金the National Natural Science Foundation of China (No. 21773304) the Fundamental Research Funds for the Central Universities(No. 2015XKZD09)+3 种基金the Natural Science Foundation of Jiangsu Province(No. BK20160240)the Research Innovation Project for College Graduates of Jiangsu Province (No. KYLX16_0549)the Research Foundation Project of Zaozhuang University (No. 2017YB24)Doctoral Foundation Program of Zaozhuang University(No.2018BS060,102201702)
文摘The underpotential adsorption of hydrogen (HUPD) is one of the most attractive fields in surface electrochemistry and electrocatalysis. In this work, the hydrogen adsorption on polycrystalline platinum electrode experimentally as well as on single crystal Pt(110) and Pt(100) electrode theoretically were studied. The effect of forced convection on the adsorption and desorption process of hydrogen was studied through adjusting the sampling rate of the microporous sampler closing to the surface of the platinum electrode immersed in dilute sulfuric acid solution. The relationship between HUPD and surface structure sensitivity was built quantitively. The DFT simulation shows that the adsorption strength of hydrogen on Pt(100), due to the lower adsorption energy, is weaker than that on Pt(110). Moreover, the bridged position of hydrogen on Pt(100) and the short-range bridged position on Pt(110) were found to be the optimal adsorption sites. The study of forced convection on the electrode surface promotes the HUPD research from static process to a convective mode and also provides a new strategy to investigate the hydrogen adsorption in solution.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.20173052 and 2020301).
文摘The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2 modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.
